code: def test_to_image_idx_real1(self):
      gidx0 = Variable("gidx0", 0, 511)
      base_idx = (((gidx0 * 4) % 32) * 32) + ((gidx0 // 8) % 32)
      base_valid = gidx0 < 256
      (idx, idy), valid = to_image_idx((4, 64, 4), base_idx, base_valid)
      print(idx, idy, idx.min, idx.max, idy.min, idy.max, valid)
      assert valid.min == 0
  
file_path: tinygrad/test/test_image_dtype.py
imports: import unittest
  import numpy
  from tinygrad import Device, dtypes, Tensor, Variable
  from tinygrad.dtype import ImageDType
  from tinygrad.features.image import to_image_idx
label_desc: Use image node_id 1 for calling the TestImageIdx obj's underlying member method code with example usage: obj.test_to_image_idx_real1() without return types